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61.
Many decapod crustaceans in marine intertidal habitats release larvae toward coastal oceans, from which postlarvae (decapodids: settling-stage larvae) return home. Decapodid settlement processes are poorly understood. Previous studies showed that in Kyushu, Japan, the callianassid shrimp population on an intertidal sandflat of an open bay joining the coastal ocean near a large estuary released eight batches of larvae basically in a semilunar cycle from June through October and that decapodids performed diel vertical migration, occurring in the water column nocturnally. We conducted (a) frequent sampling for population density and size-composition on the sandflat through one reproductive season, (b) planktonic and benthic sampling for decapodids around the bay mouth, and (c) current meter deployment at three points across the bay mouth for tidal harmonic analysis. On the sandflat, six batches of newly-settled decapodids (settlers) occurred in a semilunar periodicity until October, with peaks occurring 0–3 days before syzygy dates except for the first one. For larval Batches 1–4, buoyancy-driven shoreward subsurface currents during July to mid-October would transport some pre-decapodid-stage larvae (zoeae) toward the bay. The absence of expected settler Batches 7–8 would be due to the converse subsurface currents caused by water-column mixing and seasonal winds after mid-October, carrying zoeae offshore. Once in the bay, phasing of night and nighttime-averaged shoreward tidal current explained the settlement pattern for Batches 1–4. For Batches 5–6 occurring in mid-September to mid-October, water currents generated by seasonal wind and tidal forcings may have caused peak settlement after the time expected from tidally-driven decapodid transport. 相似文献
62.
Takafumi Watanabe Hideaki Nanamiya Manabu Kojima Shinji Nomura Shigenori Furukawa Shu Soeda Daisuke Tanaka Takao Isogai Jun-ichi Imai Shinya Watanabe Keiya Fujimori 《Translational oncology》2021,14(3):101010
PurposeEndometrial carcinoma (EC) is a clinically heterogeneous disease characterized by a number of different histological subtypes, and its heterogeneity may be involved in the accumulation of multiple genetic alterations. The aim of this work was to investigate the comprehensive mutational profile of EC tumors, and examine the associations between somatic mutations and clinicopathological features or survival in EC patients.MethodsA total of 100 surgical tumors were obtained from EC patients who had previously undergone surgery. Genomic DNA samples extracted from fresh-frozen tissues were analyzed using the Ion AmpliSeq Cancer Hotspot Panel v2 Kit, covering 50 tumor-related genes.ResultsValidated mutations were detected in 91 of the 100 tumors (91%) and identified in eight of the most frequently mutated genes, namely PTEN (57%), PIK3CA (51%), TP53 (30%), KRAS (23%), CTNNB1 (21%), FBFR2 (13%), FBXW7(10%) and RB1 (9%). PTEN mutations were found to associated with young age (< 60), early-stage, endometrioid histology, non-recurrence and better overall survival (OS). CTNNB1 mutations were associated with young age, endometrioid histology and better OS. On the other hands, TP53 mutations were associated with late-stage, non-endometrioid histology, high-grade, recurrence and worse OS. FBWX7 mutations were associated with late-stage, vascular invasion and lymph node metastasis. FGFR2 mutations correlated with deep (≥ 1/2) myometrial invasion.ConclusionOur comprehensive mutational profile will be useful for understanding and evaluating the molecular characteristics of EC tumors, and may lead to the establishment of novel treatment strategies that improve the survival of patients with EC in the future. 相似文献
63.
Maki Ohtani Jun-ichi Hikima Tae-Sung Jung Hidehiro Kondo Ikuo Hirono Haruko Takeyama Takashi Aoki 《Fish & shellfish immunology》2013,34(2):724-728
Phage display libraries are used to screen for nucleotide sequences that encode immunoglobulin variable (V) regions that are specific for a target antigen. We previously constructed an immunoglobulin new antigen receptor (IgNAR) phage display library. Here we used this library to obtain an IgNAR V region that is specific for viral hemorrhagic septicemia virus (VHSV). A phage clone (clone 653) was found to be specific for VHSV by the biopanning method. The V region of clone 653 was used to construct a 6 × His tagged recombinant IgNAR-653 V protein (rIgNAR-653) using the Escherichia coli pET system. The rIgNAR-653 protein bound specifically to VHSV, confirming its activity. 相似文献
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65.
Jun-ichi Kato 《Critical reviews in biochemistry and molecular biology》2013,48(6):331-342
ABSTRACTThe bacterial chromosome is replicated once during the division cycle, a process ensured by the tight regulation of initiation at oriC. In prokaryotes, the initiator protein DnaA plays an essential role at the initiation step, and feedback control is critical in regulating initiation. Three systems have been identified that exert feedback control in Escherichia coli, all of which are necessary for tight strict regulation of the initiation step. In particular, the ATP-dependent control of DnaA activity is essential. A missing link in initiator activity regulation has been identified, facilitating analysis of the reaction mechanism. Furthermore, key components of this regulatory network have also been described. Because the eukaryotic initiator complex, ORC, is also regulated by ATP, the bacterial system provides an important model for understanding initiation in eukaryotes. This review summarizes recent studies on the regulation of initiator activity. 相似文献
66.
Chiho Nishizawa Keizo Takeshita Jun-ichi Ueda Michiko Mizuno Kazuo T. Suzuki Toshihiko Ozawa 《Free radical research》2013,47(4):385-392
Photosensitizers newly developed for photodynamic therapy of cancer need to be assessed using accurate methods of measuring reactive oxygen species (ROS). Little is known about the characteristics of the reaction of singlet oxygen (1O2) with spin traps, although this knowledge is necessary in electron spin resonance (ESR)/spin trapping. In the present study, we examined the effect of various reductants usually present in biological samples on the reaction of 1O2 with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). The ESR signal of the hydroxyl radical (?OH) adduct of DMPO (DMPO-OH) resulting from 1O2-dependent generation of ?OH strengthened remarkably in the presence of reduced glutathione (GSH), 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), ascorbic acid, NADPH, etc. A similar increase was observed in the photosensitization of uroporphyrin (UP), rose bengal (RB) or methylene blue (MB). Use of 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide (DEPMPO) as a spin trap significantly lessened the production of its ?OH adduct (DEPMPO-OH) in the presence of the reductants. The addition of DMPO to the DEPMPO-spin trapping system remarkably increased the signal intensity of DEPMPO-OH. DMPO-mediated generation of ?OH was also confirmed utilizing the hydroxylation of salicylic acid (SA). These results suggest that biological reductants enhance the ESR signal of DMPO-OH produced by DMPO-mediated generation of ?OH from 1O2, and that spin trap-mediated ?OH generation hardly occurs with DEPMPO. 相似文献
67.
Nobuo N Noda Yuko Fujioka Takao Hanada Yoshinori Ohsumi Fuyuhiko Inagaki 《EMBO reports》2013,14(2):206-211
Atg12 is conjugated to Atg5 through enzymatic reactions similar to ubiquitination. The Atg12–Atg5 conjugate functions as an E3‐like enzyme to promote lipidation of Atg8, whereas lipidated Atg8 has essential roles in both autophagosome formation and selective cargo recognition during autophagy. However, the molecular role of Atg12 modification in these processes has remained elusive. Here, we report the crystal structure of the Atg12–Atg5 conjugate. In addition to the isopeptide linkage, Atg12 forms hydrophobic and hydrophilic interactions with Atg5, thereby fixing its position on Atg5. Structural comparison with unmodified Atg5 and mutational analyses showed that Atg12 modification neither induces a conformational change in Atg5 nor creates a functionally important architecture. Rather, Atg12 functions as a binding module for Atg3, the E2 enzyme for Atg8, thus endowing Atg5 with the ability to interact with Atg3 to facilitate Atg8 lipidation. 相似文献
68.
Hiroko Tabunoki Hiromasa Ono Hiroaki Ode Kazuhiro Ishikawa Natsuki Kawana Yutaka Banno Toru Shimada Yuki Nakamura Kimiko Yamamoto Jun-ichi Satoh Hidemasa Bono 《PloS one》2013,8(7)
Plasma uric acid (UA) levels decrease following clinical progression and stage development of Parkinson’s disease (PD). However, the molecular mechanisms underlying decreases in plasma UA levels remain unclear, and the potential to apply mutagenesis to a PD model has not previously been discovered. We identified a unique mutant of the silkworm Bombyx mori (B.mori) op. Initially, we investigated the causality of the phenotypic “op” by microarray analysis using our constructed KAIKO functional annotation pipeline. Consequently, we found a novel UA synthesis-modulating pathway, from DJ-1 to xanthine oxidase, and established methods for large-scale analysis of gene expression in B. mori. We found that the mRNA levels of genes in this pathway were significantly lower in B. mori op mutants, indicating that downstream events in the signal transduction cascade might be prevented. Additionally, levels of B.mori tyrosine hydroxylase (TH) and DJ-1 mRNA were significantly lower in the brain of B. mori op mutants. UA content was significantly lower in the B. mori op mutant tissues and hemolymph. The possibility that the B. mori op mutant might be due to loss of DJ-1 function was supported by the observed vulnerability to oxidative stress. These results suggest that UA synthesis, transport, elimination and accumulation are decreased by environmental oxidative stress in the B. mori op mutant. In the case of B. mori op mutants, the relatively low availability of UA appears to be due both to the oxidation of DJ-1 and to its expenditure to mitigate the effects of environmental oxidative stress. Our findings are expected to provide information needed to elucidate the molecular mechanism of decreased plasma UA levels in the clinical stage progression of PD. 相似文献
69.
70.
Takuya Matsushita Takahisa Tateishi Noriko Isobe Tomomi Yonekawa Ryo Yamasaki Dai Matsuse Hiroyuki Murai Jun-ichi Kira 《PloS one》2013,8(4)